title: Airborne spread and infection of a novel swine-origin influenza A (H1N1) virus.
abstract: BACKGROUND
  The novel swine-origin influenza A (H1N1) virus (S-O 2009 IV) can cause respiratory infectious diseases in humans and pigs, but there are few studies investigating the airborne spread of the virus. In January 2011, a swine-origin H1N1 epidemic emerged in eastern China that rapidly spread to neighboring farms, likely by aerosols carried by the wind.
  
  
  METHODS
  In this study, quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect viruses in air samples from pig farms. Based on two aerosol infection models (Pig and guinea pig), we evaluated aerosol transmission and infection of the novel S-O 2009 IV isolate.
  
  
  RESULTS
  Three novel S-O 2009 IV were isolated from the diseased pig. The positive rate and viral loads of air samples were 26.1% and 3.14-5.72 log₁₀copies/m³ air, respectively. In both pig and guinea pig infection models, the isolate (A/swine/Shandong/07/2011) was capable of forming aerosols and infected experimental animals at a range of 2.0-4.2 m by aerosols, but aerosol route was less efficient than direct contact.
  
  
  CONCLUSIONS
  The results indicated that S-O 2009 IV is able to be aerosolized by infected animals and to be transmitted to susceptible animals by airborne routes.
authors.affiliation: College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Daizong Street 61, Tai'an 271018, China.
authors.forename: Hongna
authors.initials: H
authors.lastname: Zhang
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Ruihua
authors.initials: R
authors.lastname: Ma
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Li
authors.forename: Yufa
authors.initials: Y
authors.lastname: Zhou
authors.forename: Hongliang
authors.initials: H
authors.lastname: Dong
authors.forename: Xinxian
authors.initials: X
authors.lastname: Li
authors.forename: Qinglei
authors.initials: Q
authors.lastname: Li
authors.forename: Mingliang
authors.initials: M
authors.lastname: Zhang
authors.forename: Zhihao
authors.initials: Z
authors.lastname: Liu
authors.forename: Baozhi
authors.initials: B
authors.lastname: Wei
authors.forename: Mingchao
authors.initials: M
authors.lastname: Cui
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Jing
authors.initials: J
authors.lastname: Gao
authors.forename: Huili
authors.initials: H
authors.lastname: Yang
authors.forename: Peiqiang
authors.initials: P
authors.lastname: Hou
authors.forename: Zengmin
authors.initials: Z
authors.lastname: Miao
authors.forename: Tongjie
authors.initials: T
authors.lastname: Chai
mesh_terms: D000391:Air Microbiology; D000818:Animals; D002681:China; D004195:Disease Models, Animal; D006168:Guinea Pigs; D053118:Influenza A Virus, H1N1 Subtype / Q000302:isolation & purification*; D009976:Orthomyxoviridae Infections / Q000635:transmission* / Q000821:virology; D060888:Real-Time Polymerase Chain Reaction; D013552:Swine; D013553:Swine Diseases / Q000635:transmission* / Q000821:virology